EFFECT OF CHICKEN MANURE AND Spirulina platensis ALGAE BIOFERTILIZER AS A PARTIAL REPLACEMENT OF INORGANIC NITROGEN IN BARHI DATE PALMS

Abstract

A field study was carried out during the years 2015 and 2016 on 25-year old Barhi date palm trees. Barhi date palms were uniform in vigour and received N as 25 to 100% mineral (inorganic) N from ammonium nitrate (33.5% N), 25 to 100 % organic nitrogen from chicken manure (2.5%N) and the biofertilizer Spirulina platensis algae at 5 to 20 ml/ palm/ year as an attempt for partial replacement of mineral N fertilizers in Barhi date palm orchards to promote yield and fruit quality and to protect our environment from pollution. All growth characteristics, flowering and fruit setting aspects, weight and length of bunch, and yield/ palm were maximized due to supplying the palms with N as 50% inorganic N + 50 % organic manure + the biofertilizer Spirulina platensis algae at 10 ml/ palm/ year. Leaf pigments and nutrients, as well as, both physical and chemical characteristics of the fruits were remarkably improved due to amending Barhi date palms with N as 25% inorganic N + 75% chicken manure + the biofertilizer Spirulina platensis algae at 20 ml / palm /year. The best results with regard to yield of Barhi date palms grown under Upper Egypt conditions were obtained due to supplying the palms with N as 50% inorganic N + 50% chicken manure + the biofertilizer Spirulina platensis algae at 10 ml/ palm/ year . Subjecting the palms with N via 25% inorganic N + 75% chicken manure + the biofertilizer Spirulina platensis algae at 20 ml/ palm / year gave the best results with regard to fruit quality. Conclusively, it might be concluded that the application of 50% inorganic N + 50% chicken manure + the biofertilizer Spirulina platensis algae at 10 ml/ palm/ year of Barhi date palm may help in improving fruit physico-chemical quality and yield at harvest time under Upper Egypt conditions.